Sharpening jig for recutter screen

ABSTRACT

For use with a novel recutter screen having a cutter or cutters capable of being resharpened, a jig for holding the screen in proper relationship to the grinder which does the resharpening.

Umted States Patent 1191 1 1,628 Paulsen Oct. 14, 1975 [54] SHARPENINGJIG FOR RECU'ITER 1,670,253 5/1928 Gilbert et a1 269/71 X SCREEN2,203,162 6/1940 Lee 51/217 R 2,459,080 1/1949 Killius 269/71 Inventor:Earl a PO. Box 2,548,944 4 1951 Chapman..... 254/133 R Round Lake, Minn.56167 2,652,243 9/1953 Reed 51/131 X 2,669,958 2/1954 Sweeney... 269/71X [22] 1974 3,066,930 12/1962 Chinnick... 269/71 [2 pp NO 44 523,266,773 8/1966 C016 254/100 Primary Examiner-Al Lawrence Smith5l/2l7l;l2;569g; Assistant Examiner MarC Davidson n 6 2 l l [58] Fieldof Search 2 9/71, 45, 54/ 021/2337 [57] ABSTRACT For use with a novelrecutter screen having a cutter or [56] References Cited cutters capableof being resharpened, a jig for holding UNITED STATES PATENTS the screenin proper relationship to the grinder which does the resharpening.1,120,798 12/1914 Duecker 269/45 X 1,125,253 l/1915 Barber 269/45 X 2Claims, 3 Drawing Figures US. Patent Oct. 14,1975 3,911,628

SHARPENING JIG FOR RECU'ITER SCREEN BACKGROUND AND SUMMARY OF THEINVENTION In my previous and co-pending application, Ser. No. 278,736,filed Aug. 8, 1972, l disclosed a novel type of recutter screen for aforage harvester. One of the chief features of that screen was the useof a resharpenable edge on the cutters so that the cutters can maintaintheir full efficiency for an extended period.

Because the screen is generally arcuate in transverse cross section, itis somewhat clumsy to handle if resharpening is to be done manually.Therefore, I have invented a jig for holding the screen and grinder inproper relationship for resharpening the cutting edge or edges on thescreen.

FIGURES FIG. 1 is a medial sectional view of my jig with a screen andgrinder shown in place,

FIG. 2 is an end elevational view similar to FIG. 1 with the screen andgrinder removed, and

FIG. 3 is a view from line 33 of FIG. 2.

DESCRIPTION Briefly my device comprises a jig which is widely adjustableto hold a workpiece such as my recutter screen in proper position. Thejig also supports a grinder in position to allow it to be swung acrossthe face of the screen to engage the cutting edge at a proper angle tobe resharpened.

More specifically and referring to the drawings, I mount my device on abase having feet adapted to rest on a workbench. These feet support alongitudinal bar or tube 11 from a bracket or end member 12. An arm 13is adjustably mounted on the bar 11 by means of a U-shaped bracket 14.This allows the arm 13 to be held in varying pivotal positions relativeto the bar 11. A rod 15 is adjustably fixed to the arm 13 by means of abracket 16. The rod is, therefore, pivotally adjustable relative to thearm, and may also be further adjustable because of the provision ofvarying attachment points at any one series of holes 17 in the arm 13.

In my preferred embodiment, the rod 15 is rotatable within the bracket16 and is screw threaded. Nut means 18 is threaded onto the rod andsupports a carrier bracket 19. The rod 15 may be provided with a crank20 which may be used to adjust the position of the nut 18 on the rod 15.The carrier 19 is adapted to hold one edge of the recutter screen 21(FIG. 1). It will be apparent that by means of all the variousadjustments, the edge can be positioned with a great deal of flexibilitywithin a considerable range of locations.

The flange 23 of the screen is also held in a variable location. This isdone by providing clamping means 24 on a lateral member 25. This memberis fixed on arms 26 which are pivotally adjustable relative to the endmembers 12 or to extension 27 thereof. Thus, the flange edge of therecutter screen is also adjustably held relative to the base, althoughthis adjustment is limited to the arcuate path defined by the pivotingof the arms 26.

The grinder 30 may be of the type in which the grinding wheel rotates onan axis at right angles to the axis of its driving motor and by whichthe grinder is usually hand-held. This grinder is also adjustablymounted. In order to accomplish this, I provide threaded rods 31extending from the extensions 27. A longitudinal bar 32 having flattenedends 33 is mounted on these rods 31. Nuts threaded onto the rods 31above and below the flattened end 33 of the bar 32 provide foradjustment of that bar toward or away from the screen 21.

A swinging bracket 35 adapted to hold the grinder 30 is mounted for freepivotal and sliding motion on the bar 32. This bracket also holds thegrinder so that it can freely pivot on an axis parallel to the bar 32.By this type of mounting, the grinding wheel will be free to sweepacross the face of the screen to grind the edge of the cutter.

It will be readily apparent that the jig is widely adjustable forvarying sizes of screen, for varying location of cutter members on thescreen, for varying curvatures of the screens, and for different makesor model of grinders.

I claim:

1. For holding a recutter screen having an arcuate body terminating inan edge on one end of the arc and a flange on the opposite end, agrinding jig comprising a base, flange holding means mounted on saidbase adapted to hold said flange, edge holding means on said baseincluding an arm pivotally mounted on said base, rod means pivoted tosaid arm and threaded at one end, said rod being rotatable, clamp meansthreadably engaged with said rod and adapted to hold said edge of thescreen whereby rotation of said rod results in adjustment of the edge,and grinder mounting means movably mounted from said base whereby agrinder can sweep across the face of said screen.

2. The device of claim 1 in which said grinder mounting means includes alongitudinal bar adjustably mounted on said base for movement toward andaway from the concave part of said arcuate body, and means swingablymounted on said longitudinal bar adapted to hold a grinding device.

1. For holding a recutter screen having an arcuate body terminating inan edge on one end of the arc and a flange on the opposite end, agrinding jig comprising a base, flange holding means mounted on saidbase adapted to hold said flange, edge holding means on said baseincluding an arm pivotally mounted on said base, rod means pivoted tosaid arm and threaded at one end, said rod being rotatable, clamp meansthreadably engaged with said rod and adapted to hold said edge of thescreen whereby rotation of said rod results in adjustment of the edge,and grinder mounting means movably mounted from said base whereby agrinder can sweep across the face of said screen.
 2. The device of claim1 in which said grinder mounting means includes a longitudinal baradjustably mounted on said base for movement toward and away from theconcave part of said arcuate body, and means swingably mounted on saidlongitudinal bar adapted to hold a grinding device.